The findings, if confirmed in future studies, could lead to a role for vitamin D supplementation in preventing this serious autoimmune disease in adults. The study was published online February 3, 2013 and will appear in the March 1 print edition of the American Journal of Epidemiology.
"It is surprising that a serious disease such as type 1 diabetes could perhaps be prevented by a simple and safe intervention," said lead author Kassandra Munger, research associate in the Department of Nutrition at HSPH.
This study provides the strongest findings to date to suggest that vitamin D may be protective against type 1 diabetes.
In type 1 diabetes (once called juvenile-onset or insulin-dependent diabetes), the body's immune system attacks and permanently disables the insulin-making cells in the pancreas. About 5% of the estimated 25.8 million people in the United States with diabetes have type 1, according to the American Diabetes Association. Although it often starts in childhood, about 60% of type 1 diabetes cases occur after age 20.
Previous studies have suggested that a shortage of vitamin D might boost type 1 diabetes risk, although those studies mostly examined the link between vitamin D levels in pregnancy or childhood and the risk of type 1 diabetes in children. Other research, in young adults, uncovered an association between high vitamin D levels and a lowered risk of multiple sclerosis—an autoimmune disease genetically and epidemiologically related to type 1 diabetes—suggesting that inadequate vitamin D in adulthood may be an important risk factor for autoimmune diseases in general.
Long-term study of military personnel
The researchers conducted a prospective case-control study of U.S. military personnel on active duty, using blood samples from the Department of Defense Serum Repository, which contains more than 40 million samples collected from 8 million military personnel since the mid-1980s. Identifying 310 individuals diagnosed with type 1 diabetes between 1997 and 2009, the team examined blood samples taken before onset of the disease, and compared the samples with those of 613 people in a control group.The researchers found that white, non-Hispanic, healthy young adults with higher serum levels (>75 nmol/L) of vitamin D had about half the risk of developing type 1 diabetes than those with the lowest levels of vitamin D (
"The risk of type 1 diabetes appears to be increased even at vitamin D levels that are commonly regarded as normal, suggesting that a substantial proportion of the population could benefit from increased vitamin D intake," said Alberto Ascherio, professor of epidemiology and nutrition at HSPH, the study's senior author.
About vitamin D
Worldwide, an estimated 1 billion people have inadequate levels of vitamin D in their blood, and deficiencies can be found in all ethnicities and age groups. While sun exposure is an excellent source of vitamin D, sunscreen, clothing, skin pigmentation, and winter months reduce vitamin D production. Food tends to be a poor source of vitamin D, with "good" sources, such as salmon and fortified milk, containing 400IU or less per serving. "Whereas it is premature to recommend universal use of vitamin D supplements for prevention of type 1 diabetes, the possibility that many cases could be prevented by supplementation with 1,000-4,000 IU/day, which is largely considered safe, is enticing," the authors said.
This study was funded by the National Institute of Neurological Disorders and Stroke (grant NS046635).
"Preclinical Serum 25-Hydroxyvitamin D Levels and Risk of Type 1 Diabetes in a Cohort of U.S. Military Personnel," Kassandra L. Munger, Lynn I. Levin, Jennifer Massa, Ronald Horst, Tihamer Orban, and Alberto Ascherio, American Journal of Epidemiology: online February 3, 2013; March 1, 2013 print edition.
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Harvard School of Public Health is dedicated to advancing the public's health through learning, discovery, and communication. More than 400 faculty members are engaged in teaching and training the 1,000-plus student body in a broad spectrum of disciplines crucial to the health and well being of individuals and populations around the world. Programs and projects range from the molecular biology of AIDS vaccines to the epidemiology of cancer; from risk analysis to violence prevention; from maternal and children's health to quality of care measurement; from health care management to international health and human rights. For more information on the school visit: http://www.hsph.harvard.edu
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Marge Dwyer | EurekAlert!
Proteomics and precision medicine
08.02.2016 | University of Iowa Health Care
Zwei neue Weltraumprojekte werden an der Universität Würzburg vorbereitet: Sie sollen unter anderem die Beobachtung von Planeten und die autonome Fehlerkorrektur an Bord von Satelliten ermöglichen. Das Bundeswirtschaftsministerium fördert die Projekte mit rund 1,6 Millionen Euro.
Wirbelstürme erkennen, die über den Mars fegen. Meteore detektieren, die auf die Erde hinabstürzen. Ungewöhnliche Blitze erforschen, die aus der Erdatmosphäre...
The University of Würzburg has two new space projects in the pipeline which are concerned with the observation of planets and autonomous fault correction aboard satellites. The German Federal Ministry of Economic Affairs and Energy funds the projects with around 1.6 million euros.
Detecting tornadoes that sweep across Mars. Discovering meteors that fall to Earth. Investigating strange lightning that flashes from Earth's atmosphere into...
Wie man bewirken kann, dass Flüssigkeiten auf festen Oberflächen fast wie ein Schlitten gleiten können, haben jetzt Physiker der Saar-Universität gemeinsam mit Forscherkollegen aus Paris gezeigt: Möglich ist das durch Beschichtungen, die an der Grenzfläche zwischen Flüssigkeit und Oberfläche ein Rutschen der Flüssigkeit provozieren. In der Folge vergrößern sich auch die mittlere Fließgeschwindigkeit und der Durchsatz. Gezeigt wurde dies am Verhalten von Tropfen auf verschieden beschichteten Oberflächen beim Übergang in den Gleichgewichtszustand. Die Ergebnisse könnten für die Optimierung industrieller Prozesse nutzbar sein, beispielsweise zur Verarbeitung von Kunststoffen.
Die Studie wurde in der Fachzeitschrift PNAS (Proceedings of the National Academy of Sciences of the United States of America) veröffentlicht.
Physicists from Saarland University and the ESPCI in Paris have shown how liquids on solid surfaces can be made to slide over the surface a bit like a bobsleigh on ice. The key is to apply a coating at the boundary between the liquid and the surface that induces the liquid to slip. This results in an increase in the average flow velocity of the liquid and its throughput. This was demonstrated by studying the behaviour of droplets on surfaces with different coatings as they evolved into the equilibrium state. The results could prove useful in optimizing industrial processes, such as the extrusion of plastics.
The study has been published in the respected academic journal PNAS (Proceedings of the National Academy of Sciences of the United States of America).
Hinweise auf einen lichtinduzierten verlustfreien Stromtransport in Alkali-Fulleriden helfen bei der Suche nach supraleitenden Materialien für die Praxis.
Supraleiter bleiben einstweilen in Nischenanwendungen verbannt. Da selbst die besten dieser Materialien erst bei minus 70 Grad Celsius ihren elektrischen...
10.02.2016 | Veranstaltungen
10.02.2016 | Veranstaltungen
09.02.2016 | Veranstaltungen